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稻飞虱是水稻的主要害虫之一.在我县主要有灰稻虱、白背稻虱和褐稻虱三种,其中以“两晚”生长后期的褐稻虱为害威胁最大.1968、1970、1972和1975年曾连续大发生,已成为夺取晚稻丰收的主要障碍.现将几年来褐稻虱发生和防治中的几个主要问题小结如下:一、发生和为害规律1.发生时期 褐稻虱第二代成虫在6月下旬开始从南方陆续迁入我县稻田,繁殖第三、四、五代三个完整世代,第六代若虫一般不能羽化为成虫,逐渐自然消亡(见表
Planthopper is one of the main pests of rice.In our county, there are mainly three kinds of gray-white louse, white-backed planthopper and brown planthopper, of which “brown rice planthopper” is most threatened in the late stage of “two nights” growth.1968,1970 , Which occurred continuously in 1972 and 1975, has become a major obstacle to seize the late rice harvest. Now several years of brown planthopper occurrence and prevention of several major issues are summarized as follows: First, the occurrence and damage law 1. Occurrence brown rice The second generation louse of louse began to migrate into the rice fields of our county from the south in late June, breeding three complete generations of the third, fourth and fifth generation. The sixth generation nymphs generally can not emerge as adults and gradually die out gradually